map transform one event to another. flatMap transform one event to zero or more event. (this is taken from IntroToRx) As you want to transform your json to an object, using map should be enough. Dealing with the FileNotFoundException is another problem (using map or flatmap wouldn’t solve this issue). To solve your Exception problem, … Read more
What is the best way to implement nested dictionaries in Python? This is a bad idea, don’t do it. Instead, use a regular dictionary and use dict.setdefault where apropos, so when keys are missing under normal usage you get the expected KeyError. If you insist on getting this behavior, here’s how to shoot yourself in … Read more
There are some libraries around there: Commons-BeanUtils: ConvertUtils -> Utility methods for converting String scalar values to objects of the specified Class, String arrays to arrays of the specified Class. Commons-Lang: ArrayUtils -> Operations on arrays, primitive arrays (like int[]) and primitive wrapper arrays (like Integer[]). Spring framework: Spring has an excellent support for PropertyEditors, … Read more
Cantor pairing function is really one of the better ones out there considering its simple, fast and space efficient, but there is something even better published at Wolfram by Matthew Szudzik, here. The limitation of Cantor pairing function (relatively) is that the range of encoded results doesn’t always stay within the limits of a 2N … Read more
$arr[$newkey] = $arr[$oldkey]; unset($arr[$oldkey]);
Server.MapPath specifies the relative or virtual path to map to a physical directory. Server.MapPath(“.”)1 returns the current physical directory of the file (e.g. aspx) being executed Server.MapPath(“..”) returns the parent directory Server.MapPath(“~”) returns the physical path to the root of the application Server.MapPath(“https://stackoverflow.com/”) returns the physical path to the root of the domain name (is … Read more
Basically it depends on the precision you need for your locations. Using DOUBLE you’ll have a 3.5nm precision. DECIMAL(8,6)/(9,6) goes down to 16cm. FLOAT is 1.7m… This very interesting table has a more complete list: http://mysql.rjweb.org/doc.php/latlng : Datatype Bytes Resolution Deg*100 (SMALLINT) 4 1570 m 1.0 mi Cities DECIMAL(4,2)/(5,2) 5 1570 m 1.0 mi Cities … Read more
Python 3+: inv_map = {v: k for k, v in my_map.items()} Python 2: inv_map = {v: k for k, v in my_map.iteritems()}
remap is an option that makes mappings work recursively. By default it is on and I’d recommend you leave it that way. The rest are mapping commands, described below: :map and :noremap are recursive and non-recursive versions of the various mapping commands. For example, if we run: :map j gg (moves cursor to first line) … Read more
This is what idmapping is suppose to do. First of all, enable is on the client and server: # echo N > /sys/module/nfs/parameters/nfs4_disable_idmapping clean idmap cache and restart idmap daemon: # nfsidmap -c # service rpcidmapd restart Now on server and the client will send instead of numeric IDs string principals like bob@YOURDOMAIN.COM. You need … Read more